Apple just posted its 2012 Supplier Responsibility Report highlighting its efforts to audit and improve working conditions within its supply chain. As part of the report, Apple also posted a list of 156 companies currently supplying components for Apple products that make up over 97 percent of all “procurement expenditures for materials, manufacturing, and assembly” of its entire product line globally.

The list includes Toshiba Mobile display, which is —as far as we know—currently not supplying displays for Apple. There were rumors in May that claimed Toshiba was working on a 4-inch retina display and rumors last month that Apple and Toshiba are building a plant for display production, which were later debunked by the increasingly unreliable DigiTimes. It also includes Sharp, who was recently rumored to be ruled out of iPad 3-panel production due to quality concerns but also supplies other components to Apple. The full list is available after the break.

In 2011, we conducted 229 audits throughout our supply chain — an 80 percent increase over 2010 — including more than 100 first-time audits. We continue to expand our program to reach deeper into our supply base, and this year we added more detailed and specialized audits that focus on safety and the environment.

Every year Apple audits suppliers in eight areas including: Anti-discrimination, Fair treatment, Prevention of involuntary labor, Prevention of underage labor, Juvenile worker protections, Working hours, Wages and benefits, and Freedom of association. The overall results can be seen in the graphic below. We also learned than Apple found 42 facilities delayed wages, 68 facilities did not provide proper benefits, and 67 facilities held back payments as punishment.

There were also 108 facilities failing to pay legal requirements for overtime and holiday pay, and 5 facilities with 6 active cases of underage labor, to which Apple is requiring the suppliers “support the young workers’ return to school and to improve its management systems.”